TS ISO 1112

TS ISO 1112 is a terminology standard for horology that defines the technical terms used for functional and non-functional jewels. In watch mechanisms, jewels are used to reduce friction, support pivots and help control wear; this standard clarifies how those concepts are named and distinguished.

How jewels are understood in watchmaking

In horological language, a jewel is usually not a decorative stone chosen for appearance, but a technical component used at specific points in a movement. Functional jewels contribute directly to bearing, support or rotational behavior, while non-functional jewels are associated with appearance or traditional usage rather than an active mechanical role. In general technical context, a vocabulary standard like this helps manufacturers, designers, watchmakers and inspectors use the same terms with the same meaning.

What this standard covers

• Technical definitions of functional watch jewels
• Technical definitions of non-functional watch jewels
• Common horological naming and term usage

The standard provides conceptual terminology rather than detailed manufacturing rules, performance limits or a prescribed test method. In watch movements, clear naming of jewels matters because it supports precise communication about the component’s role in accuracy, durability and service work.